mirror of
https://github.com/storytold/vectorcraft.git
synced 2026-10-25 18:27:02 -06:00
bflatasticandClaude Opus 5.5
9537eca5f7
A CMYK document that shows transparency is drawn once per ink plane (complemented C, M, Y; complemented K as a grey) so every blend mode, opacity, group, knockout and effect composites inks, PDF-style; the planes' inks are shown through the working CMYK profile (cached 4-D XYZ table). Cyan multiplied over magenta now shows C100 M100. Opacity masks keep screen luminance; RGB colours and placed images are separated first. RGB documents and opaque CMYK documents keep the screen-colour path. PDF export of CMYK documents writes its transparency groups with /CS /DeviceCMYK (luminosity mask groups stay RGB) and puts top-level transparency in a non-isolated page-wide group so it blends in CMYK too. Flatten Transparency composites CMYK documents ink by ink and makes CMYK regions. Non-separable modes no longer give NaN for greys. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
75 lines
3.8 KiB
Rust
75 lines
3.8 KiB
Rust
//! Flatten Transparency in CMYK documents composites inks, as the canvas shows them (M3.90).
|
|
|
|
use serde_json::{Value, json};
|
|
use vectorcraft_color::{BlendMode, Color};
|
|
use vectorcraft_doc::{AppearanceItem, Node, NodeKind};
|
|
use vectorcraft_geom::{Point, Rect, Shape};
|
|
use vectorcraft_render::Renderer;
|
|
|
|
use super::*;
|
|
|
|
fn run(s: &mut Session, id: &str, p: Value) -> Value {
|
|
s.execute(id, &p).unwrap()
|
|
}
|
|
|
|
/// A CMYK document with an unstroked rectangle of inks `cmyk` (percentages) at (10, 10) and one
|
|
/// at (60, 60), 100 pt square.
|
|
fn session(below: [f64; 4], above: [f64; 4]) -> (Session, u64, u64) {
|
|
let mut s = Session::new();
|
|
run(&mut s, "file.new", json!({"width": 200, "height": 200, "colorMode": "cmyk"}));
|
|
let mut rect = |x: f64, [c, m, y, k]: [f64; 4]| {
|
|
let id = run(&mut s, "shape.rectangle", json!({"x": x, "y": x, "width": 100, "height": 100}))["id"].as_u64().unwrap();
|
|
run(&mut s, "paint.setFill", json!({"color": {"c": c, "m": m, "y": y, "k": k}, "ids": [id]}));
|
|
run(&mut s, "paint.setStroke", json!({"none": true, "ids": [id]}));
|
|
id
|
|
};
|
|
let (a, b) = (rect(10.0, below), rect(60.0, above));
|
|
(s, a, b)
|
|
}
|
|
|
|
/// The fill colour of the flattened region at `p` in group `group`.
|
|
fn region_color(s: &Session, group: u64, p: Point) -> Color {
|
|
let doc = &s.doc().unwrap().doc;
|
|
let g = doc.node(NodeId(group)).unwrap();
|
|
let inside = |n: &Node| matches!(&n.kind, NodeKind::Path { path, .. } if path.to_bezpath().winding(p) != 0);
|
|
let r = g.children().unwrap().iter().find(|c| inside(c)).expect("a region there");
|
|
let AppearanceItem::Fill(f) = &r.appearance.items[0] else { panic!("a region has one fill") };
|
|
f.paint.color().unwrap()
|
|
}
|
|
|
|
fn picture(s: &Session) -> vectorcraft_render::Rendered {
|
|
Renderer::new().render_region(&s.doc().unwrap().doc, Rect::new(0.0, 0.0, 200.0, 200.0), 1.0, true)
|
|
}
|
|
|
|
#[test]
|
|
fn cmyk_documents_flatten_to_ink_colours() {
|
|
let _settings = crate::tests_colormgmt::GLOBAL.lock().unwrap_or_else(|e| e.into_inner());
|
|
let (mut s, a, b) = session([0.0, 100.0, 0.0, 0.0], [100.0, 0.0, 0.0, 0.0]);
|
|
run(&mut s, "transparency.set", json!({"ids": [b], "blend": "Multiply"}));
|
|
let ids = run(&mut s, "object.flattenTransparency", json!({"ids": [a, b]}))["ids"].as_array().unwrap()[0].as_u64().unwrap();
|
|
// Multiply prints both inks where they overlap.
|
|
let near = |c: Color, want: [f32; 4]| matches!(c, Color::Cmyk { c, m, y, k } if [c, m, y, k].iter().zip(want).all(|(x, w)| (x - w).abs() < 1e-3));
|
|
let overlap = region_color(&s, ids, Point::new(85.0, 85.0));
|
|
assert!(near(overlap, [1.0, 1.0, 0.0, 0.0]), "{overlap:?}");
|
|
assert!(near(region_color(&s, ids, Point::new(130.0, 130.0)), [1.0, 0.0, 0.0, 0.0]));
|
|
}
|
|
|
|
#[test]
|
|
fn every_blend_mode_flattens_to_the_canvas_pixels_in_cmyk() {
|
|
let _settings = crate::tests_colormgmt::GLOBAL.lock().unwrap_or_else(|e| e.into_inner());
|
|
for mode in BlendMode::ALL {
|
|
let (mut s, a, b) = session([20.0, 60.0, 10.0, 30.0], [70.0, 10.0, 50.0, 10.0]);
|
|
run(&mut s, "transparency.set", json!({"ids": [b], "blend": mode.label(), "opacity": 70}));
|
|
let before = picture(&s);
|
|
let ids = run(&mut s, "object.flattenTransparency", json!({"ids": [a, b]}))["ids"].as_array().unwrap()[0].as_u64().unwrap();
|
|
for p in [Point::new(30.5, 30.5), Point::new(85.5, 85.5), Point::new(140.5, 140.5)] {
|
|
let c = region_color(&s, ids, p);
|
|
assert!(matches!(c, Color::Cmyk { .. }), "{mode:?}: {c:?}");
|
|
let got = c.to_rgba8(1.0);
|
|
let want = before.pixel(p.x as u32, p.y as u32);
|
|
// The canvas rounds each ink plane to 8 bits and interpolates the profile.
|
|
assert!((0..3).all(|i| got[i].abs_diff(want[i]) <= 4), "{mode:?} at {p:?}: region {got:?}, canvas {want:?}");
|
|
}
|
|
}
|
|
}
|